Effectiveness of Ultrasound-guided Scalp Block for Supratentorial Craniotomy

Scalp block will be performed under USG guidance, using the technique described by Tsan et al. The block needle used will be an echogenic block needle, with a length of 50 mm, and a diameter of 22 G. Trained personnel comprising of the investigators in this study will perform the scalp block. Using ultrasound to identify landmarks, ropivacaine 0.375% will be administered in volumes of 1.5 ml to 3 ml. The nerves targeted will be the supraorbital, supratrochlear, zygomaticotemporal, auriculotemporal, greater auricular, lesser occipital, greater occipital and third occipital nerves.